1. Field of the Invention
The present invention relates to a caulking device for a metal plate for a tape reel in which the metal plate for the tape reel is fixed to one end surface of the tape reel.
2. Description of the Related Art
As shown in FIG. 8, a conventional tape reel 110 is composed by a disk-like upper flange 111, a cylindrical hub 112 around which a tape is wound, and a lower flange 113 integrally formed with the hub 112 and having the same diameter as that of the upper flange 111 (refer to Patent Reference 1).
The upper flange 111 has, at the central position, a locking portion 111A recessed from the upper surface of the upper flange 111 having the same size as the end surface of the hub 112. Three boss holes 114 are respectively formed away equally from the central position on the locking portion 111A. On the other hand, the three bosses 116 are integrally formed at the positions corresponding to the boss holes 114 on the end surface of the hub 112. When the upper flange 111 and the lower flange 113 are assembled, the boss 115 of the hub 112 is inserted in the boss hole 114 of the upper flange 111, and the front end of the boss 115 projected from the upper surface of the upper flange 111 is welded by an ultrasonic welder 120.
As shown in FIG. 9, the welded horn 121 of the ultrasonic welder 120 used at this time is composed so that the front end surface of the welded horn 121 has a molding portion 125 composed by a hemispherical notch portion 125A and a protrusion 125B whose the central portion is projected. When the boss 115 formed on the hub 112 is caulked to the locking portion 111A of the upper flange 111 by using the welded horn, as shown in FIG. 9, the front end of the boss 115 is formed in the shape of the molding portion 125, and a caulking portion 115A is formed. The caulking portion 115A prevents the upper flange 111 from falling out from the boss 115, and the upper flange 111, a hub 112 and the lower flange 113 are integrated.
Herein, the front end of the welded horn 121 is bit into the locking portion 111A of the upper flange 111 by the braking error of the welded horn 121, and the surface of the locking portion 111A may be curled, and risen. The welded horn 121 described in Patent Reference 1 has a melting guide portion 127 having a tapered outer peripheral end edge of the front end surface, and prevents overflowing resin from flowing in the upper direction of the upper flange 111.
[Patent Reference 1]
Japanese Published Unexamined Patent Application No. H9-320234 (paragraphs 0018, 0019, FIG. 2)
However, in a tape cartridge including such a tape reel 110, a metal plate is fixed to one end surface of the tape reel 110 for chucking the tape reel 110 in a tape drive. In this case, when the metal plate is fixed to one end surface of the tape reel 110 by using the conventional welded horn 121 to caulk the boss 115, a problem exists in that the front end of the welded horn 121 contacts with the surface of the metal plate by the braking error of the welded horn 121, and the metal plate or the welded horn 121 is damaged.
When a molding portion 125 is formed at the front end of the welded horn 121, and the caulking part 115A is formed at the front end of the boss 115, it is necessary to adjust the positions (phases) of the boss 115 and welded horn 121 correctly. That is, after the tape reel 110 is installed at a predetermined position, it is necessary to rotate the tape reel 110 in the axial surrounding direction, and adjust the phases of the boss 115 and welded horn 121. It is considered that a protrusion portion for adjusting the phases is provided on the tape reel 110 so as to adjust the phases correctly and easily, and a recessed portion is formed on the installing base of the tape reel 110. However, since the phase adjusting work itself cannot be omitted, the improvement in working efficiency is limited. A reel feed mechanism to the installing base is complicated at the time of automating the manufacturing process of the tape reel 110, and thereby a reduction in the cost of equipment is hindered.
The present invention has been accomplished so as to solve these problems. It is an object of the present invention to provide a caulking device for a metal plate for a tape reel wherein it is unnecessary to adjust the phases of a boss of the tape reel and welded horn at the time of manufacture (caulking) without bringing a front end surface of the welded horn into contact with the surface of a metal plate.